Portable, vacuum-cup-attached systems for drilling or fastening sections of aircraft fuselage or wing structures, as well as for other manufacturing operations, for other vehicle types, and for static structures, have been developed previously, but have generally been most practical for use only on workpiece areas where the contour is zero or very small in the longitudinal direction of the device. For example, some prior art vacuum cup systems could be attached readily along the flight direction of a cylindrical or otherwise highly curved fuselage, particularly where the fuselage has a long, essentially straight extent (i.e., a contour near zero), but attaching such a system to the fuselage in the circumferential direction, or fore-and-aft along a curving wing rib, would tend sometimes to produce uncertain results.
Prior art systems that use small numbers of large vacuum cups have been used, but have tended to be unable to conform smoothly to severe contours. Prior art systems with large numbers of small vacuum cups can follow a contour to some extent, but tend to be limited in the available retaining force by the necessity of having physical clearance around each vacuum cup, and by the limited available length-to-width ratio of an individual cup.
Prior art rail-mounted machine tool systems can possess the capability to advance a tool attached to a rail using a motor and gear apparatus integrated with the tool. Measurement apparatus, likewise integrated with the tool, allows the position of the tool to be determined with considerable precision. Nonetheless, prior art systems tend to be limited in their ability to conform to generalized surfaces, being best suited to positioning along low-contour paths.
Accordingly, it would be desirable to provide a method and apparatus that provides attachment of a rail system that can conform to surfaces with comparatively large contour in the longitudinal direction of traversal by the rail system and by tools carried thereon.